The present invention relates to a magnet system for nuclear spin resonance spectroscopy, in particular for in-vivo spectroscopy and tomography on a limb or a shoulder of a human body (partial-body tomography) comprising a superconductive magnet coil arrangement having coil sets arranged at an axial spacing one from the other, for generating a static homogeneous magnetic field in an examination volume, and further a coil frame carrying the coil sets and a cryostat intended for cooling the windings.
Superconductive magnet systems for partial-body tomography that have been manufactured heretofore have a geometry similar to magnet systems used for whole-body tomography, except that their dimensions are smaller. The measuring possibilities of such systems are severely limited by the relatively big distance between the field center and the outer flange. Compare for example the Bruker Biospec Systems. If such a conventional magnet system, which displays a substantially circular cylindrical shape and a room-temperature bore, is to be used, for example, for examining a patient's leg, the patient must bend his other leg or spread it off so as if he were to do the splits--an attitude which is rather uncomfortable or even impossible. There have been certain attempts at reducing the length of the systems, or at generating adequately homogeneous field areas outside the magnet structure proper (e.g. Michael Marls et al. in "New Approach to Limb Exercise-Short Magnet" in Society of Magnetic Resonance in Medicine, Book of Abstracts, Vol. 2, Eighth Annual Meeting Aug. 12-18, 1989, page 539; U.S. Pat. No. 4,721,914; EP-A-0 160 350).